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1.
S. Koh K. Konishi Y. Shiraki 《Physica E: Low-dimensional Systems and Nanostructures》2004,21(2-4):440
Self-assembled GeSiC dots stacked on a Ge hut-cluster layer buried in Si have been investigated. The critical thickness for formation of GeSiC dots is reduced owing to the strain fields from the buried hut-clusters. By utilizing the stacked structure, the dot size is decreased and the uniformity is improved. The highest density of the GeSiC dots with stacked structures is 7.4×1010 cm−2, which is six times larger than that of single GeSiC dots. The formation of the self-assembled GeSiC dots is strongly influenced by being stacked with buried Ge dots as well as C incorporation. 相似文献
2.
K. M. A. Salam Hidekazu Konishi Masahiro Mizuno Hisashi Fukuda Shigeru Nomura 《Applied Surface Science》2002,190(1-4):88-95
Polycrystalline (1−x)Ta2O5−xTiO2 thin films were formed on Si by metalorganic decomposition (MOD) and annealed at various temperatures. As-deposited films were in the amorphous state and were completely transformed to crystalline after annealing above 600 °C. During crystallization, a thin interfacial SiO2 layer was formed at the (1−x)Ta2O5−xTiO2/Si interface. Thin films with 0.92Ta2O5–0.08TiO2 composition exhibited superior insulating properties. The measured dielectric constant and dissipation factor at 1 MHz were 9 and 0.015, respectively, for films annealed at 900 °C. The interface trap density was 2.5×1011 cm−2 eV−1, and flatband voltage was −0.38 V. A charge storage density of 22.8 fC/μm2 was obtained at an applied electric field of 3 MV/cm. The leakage current density was lower than 4×10−9 A/cm2 up to an applied electric field of 6 MV/cm. 相似文献
3.
We propose a self-aligned imaging system (SAIS) using phase conjugate readout from an elementary holographic grating. The SAIS provides a huge amount of interconnections between a lot of points on two corresponding imaging planes without troublesome mechanical alignment. In the SAIS, a hologram for one-to-one interconnection is used for many-to-many interconnections. In addition, the SAIS has the capability of correcting aberration. Preliminary experiments verify the principle and the capability of the SAIS. 相似文献
4.
Atsushi Ikeda Tsukasa HatanoToshifumi Konishi Jun-ichi KikuchiSeiji Shinkai 《Tetrahedron》2003,59(19):3537-3540
In a light-to-photocurrent conversion system based on a C60-porphyrin bilayer prepared by electrostatic alternate adsorption, porphyrin units in a porphyrin polymer have been isolated by cyclodextrin utilizing the host-guest interaction. In this system, a high quantum yield was achieved by suppression of self-quenching of porphyrin units. 相似文献
5.
Atsushi Ikeda Masaru Kawaguchi Yoshio Suzuki Tsukasa Hatano Munenori Numata Seiji Shinkai Akio Ohta Makoto Ohta 《Journal of inclusion phenomena and macrocyclic chemistry》2000,38(1-4):163-170
The calixarene-fullerene interaction,which causes only a slight change in the absorptionspectra, has been substantiated by calorimetricmeasurements: the H° values arecomparable with those obtained from the associationconstants estimated by a spectroscopic method. Furthermore, we determined the association constantbetween homooxacalix[3]arene and [60]fullerenederivatives with a porphyrin moiety by fluorescencespectra. 相似文献
6.
Phase separation in the formation of hollow particles by suspension polymerization for divinylbenzene/toluene droplets dissolving polystyrene 总被引:1,自引:0,他引:1
Phase-separation behavior within polymerizing divinylbenzene/toluene droplet dissolving polystyrenes (PS) was investigated to clarify the formation mechanism of the hollow polymer particles by suspension polymerization. No hollow particles were obtained at a low content of low-molecular-weight PS where phase separation occurred at high conversion. On the other hand, hollow particles were obtained at a high content of high-molecular-weight PS where phase separation occurred at low conversion. The phase separation in an early stage of the polymerization, which was promoted by the presence of PS and cross-links of polydivinylbenzene, was a key factor for the formation of the hollow structure. 相似文献
7.
Satoshi Ito Kazuya Koizumi Katsuhiko Fukuda Naohiro Kameta Tsukasa Ikeda Toru Oba Kazuhisa Hiratani 《Tetrahedron letters》2006,47(48):8563-8566
A new series of BINOL-based macrocycles with two phenolic protons have been synthesized via oxidative coupling reaction using CuCl(OH)-TMEDA. 相似文献
8.
Kazuhiro Kobayashi Atsushi Takanohashi Kenichi Hashimoto Osamu Morikawa Hisatoshi Konishi 《Tetrahedron》2006,62(44):10379-10382
A facile synthetic method for 4,5-diaminopyrrolo[1,2-a]quinoline derivatives has been developed. Treatment of 2-(pyrrol-1-yl)benzaldehydes with secondary amine hydrochloride/NaI/TMSCl/Et3N in the presence of an isocyano compound leads to the formation of 4-alkyl(or aryl)amino-5-dialkylaminopyrrolo[1,2-a]quinolines. 相似文献
9.
8-Amino-s-triazolo[4, 3-b]pyridazine (I), an adenine analog has been prepared by two different routes. Likewise 8-amino-3-phenyl-s-triazolo[4,3-b]pyridazine (V) has been prepared. Both of these compounds have been prepared utilizing 3,4,5-trichloropyridazine and 3,4,6-trichloropyridazine as the starting materials thus interrelating the 3,4,5-and the 3,4,6-series. A variety of other transformations have been carried out. 相似文献
10.
Chiral β-dimethylaminoalkylphosphines were prepared starting with amino acids, (S)-alanine, (S)-phenylalanine, (R)-phenylglycine, (S)-valine, and (R)-tert-leucine. The chiral phosphines were found to be highly efficient ligands for a nickel catalyzed asymmetric Grignard cross-coupling reaction (38~94% optical yield). 相似文献